I just installed the A3-L on a FMS BF-109F to assist the rudder only. I saw Pilot Ryan’s video and he recommended 75% gain. But I find the gain affected the throw of my rudder input i.e. the deflection hits end points when I move the stick only a quarter. The only gain setting where I can utilize my full range of stick is 0%. Why does the gyro gain affect sensitive of my stick input? That does not make sense at all. HELP please?

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I just installed the A3-L on a FMS BF-109F to assist the rudder only. I saw Pilot Ryan’s video and he recommended 75% gain. But I find the gain affected the throw of my rudder input i.e. the deflection hits end points when I move the stick only a quarter. The only gain setting where I can utilize my full range of stick is 0%. Why does the gyro gain affect sensitive of my stick input? That does not make sense at all. HELP please?

You should have noticed a similar trait with the AIL and ELE. High gain usually causes the control surface to feel numb and not go full throw. It may reach "end point" early but you shouldn't be getting full throw. Zero gain generally gives you no stabilization and thus, the stick does what it would do if there was no stabilizer installed. Additionally, it also depends on whether you've got the A3-L on stabilized mode (blue light) or 3D mode (red light). I find that 3D mode can sometimes make the plane do funny things.
Finally, I don't normally bother with hooking up rudder to the stabilizer. The yaw axis isn't as affected in flight as the other axis and on the ground having high gain on the rudder can make the plane wander or veer off to the side from ground bumps and cross winds. The stabilizer can over correct. If you must have the rudder hooked up the A3-L, then just go 50% or less. Depending on the plane, the faster the plane goes, the more need to use less gain as the plane can start to "jutter" as speed increases. Have the gain hooked up the the rotory knob (AUX3) so you can adjust in the air. Dial it up till it starts to jutter at full speed, then dial it down just enough to stop the juttering. Do it at altitude and know which way to turn the knob. You want to be in the blue.

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Thanks Xviper. I flew the BF-109 and it really does not need stabilization during flight. However, It’s notoriously hard to handle on takeoff/landing run and It swerves out of control before I can react with rudder (I am a competent tail dragger pilot and grease landings 95% of the time). Even pilot Ryan has reservations flying it sans stabilization (see below)

Anyway, I just need a little gyro assistance to keep the 109 tipping from on it’s wings during ground roll, so only connected the rudder to Gyro. Also flying the full house plane on a 6 channel receiver so no spare channel for dialing gain in flight, keeping it in normal mode permanently.

I reduced gains to 20%, I also reduced my rudder Servo end Point adjustment to 100% from 125% to allow gyro gain above 0 before hitting end point prematurely.

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A taildragger like that with narrow main gear can have very difficult ground handling. Taxi-ing out and back in is not a problem as you hold full UP elevator to keep the tail wheel forced onto the ground to help it steer. However, the take off roll (and maybe even the landing roll) can be problematic. On a paved runway, a gyro on the rudder may help to a certain extent but it's better to learn what it takes to get it rolling straight till it's off the ground. On bumpy ground, a gyro on the rudder for take off roll is not very useful. It can over compensate and veer way off course.
When taking off with this kind of plane, I find it much better to get the thing rolling quickly till there is enough airspeed for the wings to almost lift. Ease off on the UP elevator as it lifts off. It doesn't look very realistic but getting the plane off with all 3 wheels at the same time is a better way to handle such a plane. Rolling on the ground on just the mains, especially when they are so narrow and splayed out like the 109, makes for a very darty roll. Once in the air, there is less fuss.

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Can i mount this gyro backwards? Pins facing the nose? I think i did this before and it worked but this was long ago i dont remember.

I think it's possible. You just have to reverse the roll and pitch response.

From page 1 of the manual ...........................
"The gyro can be attached flat or upright. In the example on the right, we just show you 2 ways of many different orientations. You only need to ensure that the servo connector pins always point toward the front (or rear) of the plane."

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Hey guys, just got my first A3-L. It’s going to be connected to the 3-way mode switch on my DX8 and AR8000 rx . I don’t need/want the 3D flight mode in gyro, and I’m concerned what’s going to happen if I inadvertently move the switch to position 3. The A3-L manual says “The normal gain (Basic Gain) (GAIN1) will take effect in all flight modes, it’s the most basic feature of the gyro, don’t turn it to 0% anyway.” Does this mean that if I have the Gain 2 pot on the gyro set to 0% and I move the switch to position 3 it will effectively just stay in normal 2D (“basic gain”) mode?

Thanks in advance for any advice!

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Hey guys, just got my first A3-L. It’s going to be connected to the 3-way mode switch on my DX8 and AR8000 rx . I don’t need/want the 3D flight mode in gyro, and I’m concerned what’s going to happen if I inadvertently move the switch to position 3. The A3-L manual says “The normal gain (Basic Gain) (GAIN1) will take effect in all flight modes, it’s the most basic feature of the gyro, don’t turn it to 0% anyway.” Does this mean that if I have the Gain 2 pot on the gyro set to 0% and I move the switch to position 3 it will effectively just stay in normal 2D (“basic gain”) mode?

Thanks in advance for any advice!

That's pretty much it. I only ever use the "normal" gain for normal flying. I don't fly 3D so I've turned the second gain pot all the way off. I also have planes that are on an 8-ch Rx and I plug the master gain into AUX3 and use the rotary knob for gain adjustments on the fly. Set the basic gain pot about 1/2 or less (<12 o'clock). This will give you a range of less than 50% to zero %. I find that on most of my planes, an actual gain of around 25% is very adequate. The 3rd position is for gyro OFF. I don't even plug the mode into a switch control. The gyro is simply controlled by the rotary knob. You can actually turn off the gyro with the knob set to zero gain. I find the mode switchability to be quite useless so I don't bother with it at all.
In general, it's the AIL that will stutter first if the gain is too high. Fly the plane as fast as it will go and set the gain just below when it starts to AIL oscillate.

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That's pretty much it. I only ever use the "normal" gain for normal flying. I don't fly 3D so I've turned the second gain pot all the way off. I also have planes that are on an 8-ch Rx and I plug the master gain into AUX3 and use the rotary knob for gain adjustments on the fly. Set the basic gain pot about 1/2 or less (<12 o'clock). This will give you a range of less than 50% to zero %. I find that on most of my planes, an actual gain of around 25% is very adequate. The 3rd position is for gyro OFF. I don't even plug the mode into a switch control. The gyro is simply controlled by the rotary knob. You can actually turn off the gyro with the knob set to zero gain. I find the mode switchability to be quite useless so I don't bother with it at all.
In general, it's the AIL that will stutter first if the gain is too high. Fly the plane as fast as it will go and set the gain just below when it starts to AIL oscillate.

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I received a Mirage with a A3L installed. There are 2 adjustableGain pots labelled #1 and #2. Can you please tell me what each of them controls. Thank you.

One is "normal" gain and the other is "3D" gain. (They control all the axis - all control surfaces that you have plugged into it.) Since you aren't likely to do 3D with a Mirage, turn that one off (full counter clockwise) - I believe that's the one on the right. The "normal" one on the left can be dialed in at around 10 O'clock. However, if you are using master gain on the rotary knob of your TX, then you can start with it a bit more and use the knob to adjust gain on the fly. Start low. You can get the manual to download from Motion RC on the A3-L page. That will explain things in far more detail. Nevermind. Here it is ...............................https://cdn.shopify.com/s/files/1/10...57732900112653

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Does anyone know why every min or so the gyro twitches? (Like a sudden jolt) It doesnt bother me in flight but perhaps im doing something wrong? Im not using the included capacitor (or any at all). Thanks

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Does anyone know why every min or so the gyro twitches? (Like a sudden jolt) It doesnt bother me in flight but perhaps im doing something wrong? Im not using the included capacitor (or any at all). Thanks

The voltage capacitor is a good place to start . Mine all sit still after getting the wiggle just after powering up like it should .